Virtual machine live migration method, virtual machine memory data processing method, server, and virtual machine system

A virtual machine live migration method and a server, to resolve a problem that live migration of a virtual machine cannot be implemented in an SR-IOV technology scenario. According to the virtual machine live migration method and the server in the embodiments of the present invention, by setting a dirty write flag, a virtual PCIE device of a to-be-migrated virtual machine performs at least one read and write operation on received data; a virtual machine manager of the to-be-migrated virtual machine can identify a change in the data and migrate changed data to a destination virtual machine, thereby resolving a problem in the prior art that data cannot be migrated during a virtual machine live migration process because the data passes through the virtual PCIE device but the virtual machine manager cannot perceive the data.